Why does it get more difficult to push a beach ball underwater as you go deeper?

Answer 1

It's harder to push a beach ball underwater because it displaces more water than it weighs. (Gravitational Force is less than Buoyant Force)

Answer 2

When you push a floating object down it has to move water out of the way - it makes room for itself. Whatever weight of water is displaced, that's how hard you have to push : the deeper the harder. If you leave the object alone, it will descend into the water until the weight of water displaced is the same as the weight of the object. That is why the weight of a ship is always referred to as its displacement.

Answer 3

As more of the ball is submerged, you increase the volume of water being displaced. The difference between the density of the water and that of the air inside the ball generates an upward force, or buoyancy, on the ball.

Once the ball is totally submerged, there should be no difference in the weight (force) required to sink the ball farther into the water, because although the pressure in the water is higher at an increased depth, its density does not change substantially. The difference in density between the water and the air in the ball remains the same. At greater depth, the ball will actually decrease in volume, and the air inside will increase in pressure, as a result of the water pressure on the flexible ball.

Answer 4

Because you are also having to push water out of the way of the ball. If you meant push it INTO the water, it is buoyant- it wants to float. It is being pushed up by the weight of the water it displaces.